This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A211610 #13 Jun 06 2021 09:04:49
%S A211610 4,224,161312,1683907808,256213978094784,575112148876911852416,
%T A211610 19248204431728945392010740480,9687459136669902998216039379883774976,
%U A211610 73815961078227084527800998811241905249902260224,8562177846610881578580018959490439733543225146878872883200
%N A211610 a(n) = Sum_{k=1..n-1} binomial (2*k, k)^n.
%C A211610 2^n divides a(n).
%C A211610 p divides a(p) for prime p of the form p = 6k + 1.
%F A211610 a(n) = Sum_{k=1..n-1} binomial(2*k, k)^n.
%F A211610 a(n) ~ exp(3/8) * 4^(n^2-n) / (Pi^(n/2) * n^(n/2)). - _Vaclav Kotesovec_, Mar 03 2014
%t A211610 Table[ Sum[ Binomial[2 k, k]^n, {k, 1, n - 1}], {n, 2, 13}]
%Y A211610 Cf. A211611, A238717.
%K A211610 nonn
%O A211610 2,1
%A A211610 _Alexander Adamchuk_, Apr 17 2012